A flaw in the Linux kernel’s btrfs filesystem driver causes a memory leak: when btrfs_map_block() exits early with the error code -EINVAL, the chunk map it just retrieved is not released. The leak accumulates kernel memory over time, which can eventually exhaust available memory and result in a denial‑of‑service condition for the entire system. The weakness identified is a failure to free a resource (CWE‑772).

Any Linux kernel running the unpatched btrfs filesystem code is affected. The advisory lists no particular version numbers; the fix resides in the commit that replaces the buggy logic. Distributions or custom builds that have not incorporated that commit remain vulnerable until they upgrade to a kernel including the patch.

The flaw is local to the kernel and would require the attacker to be able to repeatedly trigger the failing path of btrfs_map_block(), such as by mounting or accessing Btrfs volumes. The CVSS score of 5.5 indicates medium severity. The EPSS score is not available, and the vulnerability is not in the CISA KEV catalog. The likely attack vector is inferred as local code execution that can invoke the vulnerable filesystem operation. There are no public exploits known, but sustained use of the flaw could lead to resource exhaustion and service disruption.